This invention relates to a method and apparatus for use on an aircraft to substantially minimize the total fuel consumed by the aircraft during a flight.
A significant part of the total cost of operating an aircraft is attributable to the cost of fuel expended during any given flight, and this cost is reduced to the extent that total fuel consumption for a flight is minimized. In the past, pilots have attempted to minimize the quantity of fuel needed for a given flight by pre-planning the flight with the aid of such information as expected weather conditions, performance information relative to the particular aircraft, and handbook data relating to courses, speeds, etc.
A number of in-flight pilot aids and control systems have also been used or suggested in the prior art for minimizing aircraft fuel consumption. Some of these utilize stored data of the type available from handbooks while others utilize real-time data sensed and processed from time to time during the flight by equipment on the aircraft. Some of these control systems provide automatic adjustment of aircraft controls while others simply provide a reference for the pilot, and some of the systems offer more than one operating mode for selection by the pilot as appropriate.
For example, in U.S. Pat. No. 3,221,759 issued to T. A. Banning, Jr., instruments are disclosed for controlling operations, as for example in a propeller-driven aircraft, to provide maximum economy of operation. This patent describes an iterative approach to the maximizing of operating economy through measured parameter sampling and comparison.
In the Canadian Pat. No. 851,576 issued to Arnold Guetta, a method and apparatus are disclosed for securing increased operational efficiency in a powered vehicle. According to the disclosure of this patent an operating mode is first selected, and this selection together with certain sensed inputs is provided to an analog computer which controls fuel flow. In some of the modes certain of the sensed inputs are selected and combined for comparison with preselected stored criteria of high efficiency, and in other modes the sensed inputs are provided to the computer and the throttle is automatically adjusted in response to a comparison of successive computed values based on the corresponding sensed inputs.